The present invention generally relates to railcar braking systems. More particularly, the present invention relates to a relay valve based accelerated brake pipe application and release system for passenger railcars having a modulated brake pipe.
In prior art railcar braking systems, the functions of accelerated application and release of brakes on a railcar were normally performed by pneumatic devices. These pneumatic devices are large, heavy, and not contained in a single unit. The pneumatic devices must send their signals in series from one car to the next, allowing for significant periods of time to pass pneumatic signals to an entire train, especially trains with considerable number of cars. Also, it takes considerable time and expense to maintain the various pneumatic valves currently used to perform the accelerated application and release functions so they perform at peak levels. More recently, as is known in the art, prior art devices also offer an electro-pneumatic xe2x80x9coverlayxe2x80x9d to perform certain functions, but these xe2x80x9coverlaysxe2x80x9d do not reduce the number of pneumatic devices on a railcar.
In one aspect, the invention provides a relay valve based accelerated brake pipe application and release system having an electronic control module. A source of fluid pressure is connected to a valve mechanism for receiving and transmitting fluid pressure signals. The valve mechanism has a fluid connection to an exhaust to atmosphere. There is an accelerator volume having a predetermined volume and a fluid connection to the valve mechanism for storing a predetermined volume of fluid. Included is a brake pipe transducer electronically connected to the control module and which has a fluid connection to the valve mechanism for transmitting a first pressure signal to the control module. There is a cut-out solenoid valve electronically connected to the control module and includes a fluid connection to the brake pipe transducer for receiving at least one of a cut-in and a cut-out signal. An emergency solenoid valve is electronically connected to the control module and it has a fluid connection to the cut-out solenoid valve for receiving an emergency signal. A cut-out device is included for opening and closing a fluid connection and it has a fluid connection to the emergency solenoid valve. Also an application solenoid valve is electronically connected to the control module and has a fluid connection to the cut-out solenoid valve for receiving an apply signal and for transmitting a pilot pressure to the cut-out solenoid valve. There is a release solenoid valve electronically connected to the control module and it has a fluid connection to the cut-out device for receiving a release signal and transmitting a pilot pressure to the application solenoid. The final essential element is a control transducer electronically connected to the control module and including a fluid connection to the release solenoid for transmitting a second pressure signal to the control module.
It is the primary object of the present invention to provide a relay valve based accelerated brake pipe application and release system which offers accelerated service friction brake application and release functions for inactive hauled passenger rail cars.
It is another object of the present invention to provide a relay valve based accelerated brake pipe application and release system which offers integrated accelerated service friction brake application and release functions with an electro-pneumatic means of controlling the brake pipe pressure.
It is a further object of the present invention to provide a relay valve based accelerated brake pipe application and release system which uses multiple diaphragm relay valve technology to integrate the functions of friction brake application and release.
It is still another object of the present invention to provide a relay valve based accelerated brake pipe application and release system which offers improved size, weight, and overall packaging of brake pipe control devices used on locomotive and rail cars.
It is even yet another object of the present invention to provide a relay valve based accelerated brake pipe application and release system which offers an electro-pneumatic brake pipe control function that is better integrated with all pneumatic back-up functions.
It is still a further object of the present invention to provide a relay valve based accelerated brake pipe application and release system which allows railcars equipped with this type of device to be run in trains having cars with older all pneumatic brake pipe control systems.
It is still even another object of the present invention to provide a relay valve based accelerated brake pipe application and release system which allows a train controlling car or locomotive to use the same items of electro-pneumatic brake pipe control as the cars that are performing brake pipe enhancement/overlay functions.
In addition to the above-described objects and advantages of the relay valve based accelerated brake pipe application and release system, various other objects and advantages of the present invention will become more readily apparent to the persons who are skilled in the same and related arts from the following more detailed description of the invention, particularly, when such description is taken in conjunction with the attached drawing figures and the appended claims.